Since it has been demonstrated in this laboratory that the acceleration of protein synthesis in accessory sex tissue following the administration of estradiol and testosterone is secondary to an acceleration of messenger RNA synthesis in the nuclei of the cell the proposed experiments will consist of a systematic analysis of the events leading up to this enhancement. The following studies have been planned to be continued: 1. An analysis of the specificity of attachment of progesterone-1, H3 on the chromosomes of the hen oviduct under varying growth conditions. 2. An investigation of the chromosomal attachment of testosterone-1, H3 in the nuclei of the rat prostate utilizing ultracentrifugation techniques. 3. An attempt to isolate and characterize the nature of the binding protein of the chromosomes to which the hormones are attached.